This relates generally to sensors and, more particularly, to proximity sensors for electronic devices.
Some cellular telephones contain proximity sensors. A proximity sensor can detect when a cellular telephone has been brought into proximity to a user's head. When the cellular telephone comes into close proximity to the user's head, touch screen functions in the cellular telephone can be deactivated to avoid unintentional touch input.
A cellular telephone proximity sensor generally contains a light-emitting diode that emits infrared light and a corresponding infrared light sensor that measures the amount of emitted infrared light that is reflected back to the infrared light sensor from the user's head. In some circumstances, such as when a user's hair is dark, the amount of reflected light from the user's head may be relatively small. Unless care is taken, proximity sensor signals will not be sufficiently accurate to properly deactivate a touch screen.
It would therefore be desirable to be able to provide improved proximity sensors for electronic devices.